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Wednesday, May 31, 2017

GREETINGS! Last week, a new paper I've literally been working on since I finished my PhD has FINALLY been completed! Its easily my largest monograph at the moment and includes a whopping 14 new species, 3 new genera and a new subfamily!

The paper focuses on a group of tropical shallow/deep goniasterid sea stars which include reef setting genera such as Neoferdina but also seldom studied genera such as Ferdina and their relatives. I actually ended up describing 3 additional new genera and MANY new species!

The whole thing is a lot to unpack.. and so here's some take away lessons that I thought I would share from writing it!

1. Citizen Science & Social Media Made a Significant Contribution! I've talked about this before.. the world is flooded with divers, photographers and interested people with cell phones all over the world! Thanks to a combination of museum collections and divers I was able to identify and describe several new species and even add color variation to poorly known species in the group I published on! Many times these get misidentified as people try to "shoehorn" them into known species in field guides. This new species for example, Neoferdina oni from the Philippines! I actually identified this species based on material collected by the California Academy of Sciences from one of their recent expeditions (such as this one)

I will likely do a separate post on the etymology of these new species a bit later, but the species epithet of this one "oni" represents a horned demon from Japan which alludes to the two spines on each plate along the side!

Images such as this one gave me more insight into how the colors vary in already established species! and provide leads to possible NEW species...

2. The Mesophotic Zone: New studies and new Species! There's a depth region in the ocean that falls just below "coral reef" (~30m) depth but just above the "deep sea" (above 200m).. that's roughly between 100 and 500 feet. More about this area here. and this entire website devoted to this area! This area is also known as the "Twilight Zone" aka the "sub Reef area" and contains a fauna that is related and similar but distinctly different from those seen at the surface. The California Academy of Sciences's research division as well as their Steinhart Aquarium have both been studying this area in the Philippines. In 2015, they collected this lovely beast, (and here was a news account showing it off) which I had also been observing in the Paris collections from areas throughout the Indo-Pacific!I initially identified it as a familiar genus, Neoferdina, but eventually realized it was actually a separate and undescribed genus which I named Bathyferdina!

I've actually been describing Mesophotic Zone starfish for quite a long time. Here was Astrosarkus idipi from many years ago aka the "Great Pumpkin Starfish" and there were several more as well...One important take away message: Describing new species is PART of understanding the biology of a NEW ecosystem. This was the same thing that happened with understanding all of those predatory coral starfish.. new species led to understanding each "character" of a new ecosystem!3. Museums & Travel: Where the New Species Roam
Here's a neat new species from the western Indian Ocean-Madagascar and the east coast of South Africa.. Ferdina mena! Identified by the two distinctive bald patches present in each interradius (i.e. the "armpit") of the starfish.

Thanks to the stunning photos of "Optical Allusion" I was even able to find living images of this species in South Africa!

I have a strangely long history with this species.. I identified one of these (mistakenly) for the field guide Coral Reef Animals of the Indo-Pacific by Terry Gosliner, Gary Williams, and Dave Behrens- as Ferdina sadhensis which was known only from Oman.

During one of my recent visits to Paris and the Museum national d'HIstorie naturelle in Paris, I discovered that this wasn't just an odd specimen with the twin bald, red spots in each interradius..it was present on ALL of the specimens collected from a collection made from Madagascar!!

Following this, I was visiting the Iziko Museum in South Africa in 2015 and discovered the SAME species from the east coast of South Africa! Citizen scientists in South Africa also showed me MANY photos of starfishes which confirmed the specimens.

and to return to the citizen science angle.. images on Flickr further showed this species in Mozambique as well as further color and pattern variation of this species from South Africa thanks to photographer Derek Keats and others!

In both cases, these specimens had been collected and sitting in these museums awaiting discover for YEARS. In Paris-2007 and 2010 and from the Iziko Museum collections-in 1986!!!

For one of the new species I had discovered, Paraferdina plakos, I only had one or two individuals on which to base my new species description. Were they the same? Was it variation? How do different individuals differ from one another? Are the defining characters the same across the species range?

SO, I took advantage of some aspects of the internet which I usually list as pet peeves...

1. Misidentified species made by people who don't want/need to figure out the correct species
2. Pictures of species collected by Internet aquarium and pet shops

I was actually able to make OVER TWENTY OBSERVATIONS of this species misidentified as the common "peppermint star" Fromia monilis!!

This led to ANECDOTAL information about its color and how individuals varied in shape. One or two sites actually were pretty up front about declaring how their specimens had been collected from Sri Lanka, suggesting a further occurrence point for this species.

What does this tell us? Not ONLY are A LOT of new species yet to be discovered but we are ALREADY seeing them sold in the pet trade.. and with no correct identifications by scientists to recognize them, are they endangered? For a species that has just been described we know NOTHING bout its reproductive biology, populations, can they handle the strain of being "fished" for this trade???

In this newly discovered genus and species from New Caledonia, Kanakaster solidus shows these crystalline bodies as a sort of pebbling all over the body surface, which is pretty suggestive of the microlens idea.. but I suppose they could also be incipient or underdeveloped granules which cover the body surface as almost a kind of thick tissue.

from Kankaster solidus, holotype

Whereas, in this species, Kanakaster discus, the crystalline structures are actually arranged in stellate formations rather than simply as granulated pebbling. Much more suggestive of a "lens" type function I would think.. but hard to say without more data.

from Kanakaster discus, holotype

If these ARE lenses? Why do the patterns differ? Some "lenses" are present in shallow-water species whereas others are present in deeper water species! And how are the patterns adaptive? If that's indeed the case?

Many, MORE questions! and probably at least one more post about these newly discovered animals!

Since I wrote that introductory post in 2008 not only have I learned more about it-but we've now seen it ALIVE all over the Atlantic and the tropical Pacific thanks to the livestream videos of Okeanos Explorer!

During the course of Katie's research she collected a fair amount of cool "anecdotal data" which amounts to singular observations and some other stuff which furthers the "natural history observation" of a starfish about which we know very little! So her observations along with some further observations from the 2017 research legs of the NOAA Okeanos Explorer, some further homework on my part and voila!

Let us learn MORE about the weird starfish Tremaster mirabilis!

1. It eats coral (possibly)Probably one of the BIGGEST questions I had for such a strange looking sea star! As we'll see, this species is seen quite a bit and yet one of the most immediate questions about it seemed elusive!Fortunately Katie Gale was quite lucky and was able to capture and image of this specimen of T. mirabilis taken by the fine people who operate the Remotely Operated Vehicle ROPOS/DFO. Gale's paper cites this image showing our mysterious starfish feeding on CORAL! Specifically the octocoral Acanthogorgia!

Tremaster mirabilis occurs widely around the world and of course, its always possible that there is variation in feeding or that possibly the animal in the picture has somehow been caught doing something completely else that we have no clue about-BUT our best guess is that its feeding. So, we continue on with that notion..

BUT we have THIS image taken on Whaley Seamount during Leg 3 of the Okeanos Explorer mission at 875m!

Could its location on the rock surface be because its near a yummy food source? Another coral predator to add into our understanding of deep-sea coral ecosystems???

2. Time lapse movement and?? This probably seems like a common sense thing-we KNOW starfish move albeit VERY slowly. and can actually show some behavioral complexity (here)Katie nabbed some of this GREAT video showing this species moving around its aquarium and more importantly NOT attacking this sea anemone in the aquarium.This is actually an important point because we know MOST starfish CAN move but they often don't.
So, ACTUALLY capturing it doing so gives us some insight into what they do when we aren't watching them..

Katie for example caught THIS unusual variation in posture: Could this be avoidance of the bottom somehow? Filter feeding? Some kind of stress response?

Note in this image that the "skirt" is lifted compared to the in situ Okeanos images below where the animal is flush with the bottom..

What is it doing?? This is a bit of a A mystery.

and on Pau Pau Seamount and elsewhere Tremaster is CRAAZY abundant! Are they moving around to feed? to reproduce? How does all of this come together??? These behavioral bits add to our understanding but also to the mystery!

If we sped the movement of this "constellation" of Tremaster mirabilis up, would we still see no movement? or is it a Times Square of Deep-Sea Starfishes???

3. One species lives in at LEAST THREE Oceans?
It USED to be that everything we knew about this species was taken from museum specimens and indeed we are STILL dependent on samples from throughout the world for new records of where many species live.

There is some question about whether or not this one species "Tremaster mirabilis" is actually one species or possibly several 'cryptic' species disguised by the fact that all the individuals observed all appear to be the same.

The external characters vary only slightly and its not unusual for a widely occurring species to demonstrate some... variation throughout its range. However, when we examine dead museum specimens we are often missing data such as color and behavior which can be important. Especially when its range where it lives is at least THREE oceans!Tremaster is a moderately occurring deep-sea species.. occurring roughly between 200 and 600 m

Thanks to submersibles such as Okeanos Explorer we now have VIDEO and ON SITE (in situ) observations of LIVING animals!

Tremaster mirabilis is supposed to be one species..but as you can see there is a SLIGHT difference in body form..

North & Central Atlantic:An image from Nygren Canyon (top) and the lower image from Puerto Rico. Note there's more of a "skirt" around the edge versus the Pacific ones.

Throughout the tropical Pacific

Here's a brilliant deep-orange one seen on the recent Okeanos leg from Jarvis Island..

And interesting brick colored one from Pau Pau seamount

and this interesting lighter colored individual from Baker Island..

Other Records show this species in New Caledonia and throughout the Pacific. I've not yet seen it from the Indian Ocean however..

4. There are Jurassic FossilsAs if dealing with living animals weren't enough, these intriguing beasts show a CLEAR relationship to at least TWO Jurassic fossils!
Bear in mind that the Jurassic is quite a LONG time ago. These sea star were living in the world's oceans while dinosaurs roamed the Earth!

5. What does "Tremaster" actually mean? And"brood chambers"??
FINALLY! What does the genus "Tremaster" actually MEAN anyway? "aster" is obviously "star" but it turns out "Trema-" refers to "aperture" or OPENING!

When Addison Emery Verrill described this genus in 1880 he made allusion to these FIVE openings present in each interradius! These were one of the distinctive characters he used to diagnose his (then) new genus!! and "mirabilis" of course refers to "wonderful"

Here's a photo of the underside of a Tremaster specimen.. the openings are indicated by yellow circles!

So, as it turns out if you look more CLOSELY at these openings, they are actually OPENINGS into chambers present INSIDE and THROUGH the body wall and open up on the TOP:

Here are images of a dissected individual from the underside showing these openings (i.e. these are close ups of what's in the yellow circles above)

According to the author who described this species (and subsequent literature), there are actually BROODED young in these chambers! Its not clear to me if they are simply embryos or actual juvenile individuals. Strangely enough, these have not been documented..at least not in the literature that I could locate. and I have yet to actually spot them. But perhaps I've simply not been looking at the right ones...Thus, the openings appear to provide an opening for water to circulate into these chambers which could serve any number of purposes.. Possibly to aerate the "brood" chambers? Or perhaps they assist in the degree of arching the dome-like shape is capable of?? Filter feeding? Predation?? One of the great things about science is how it marches on! Its been 9 years (!!) since I wrote that first post and I LOVE that what in addition to what I've learned from reading, there has ALSO been genuine progress in learning NEW information on the biology of these animals.. And one of these days we will more FULLY understand it and its strange signficance!

Also GREAT to see that animals like this INSPIRE! Here is a GREAT illustration of this species by "Cartoon Neuron" on Twitter...

The Okeanos Explorer was surveying Jarvis Island in the central Pacific at a depth of about 400 to 500 m. They were watching a tiny squid swimming through a thicket of deep-sea "bushes" composed of hydroids and worm tubes, covered by many, MANY animals including brittle stars!

Most times we see brittle stars, they have their arms up in the water, presumably filter feeding... Brittle stars are frequently numerous as I've written about here.

The tiny squid (apparently in the genus Abralia (as identified by Mike Vecchione at NMFS) was moving along its merry way..when suddenly.... (at 0:25 to 0:30) the tiny squid is knocked around and then CAUGHT by the arm of one of the ophiothricid brittle stars!!!

Yes! Most of us don't think of sea stars OR brittle stars as capturing fast moving or SWIMMING prey! Strangely enough, THIS WAS CAUGHT ONCE BEFORE!!

Once, back in 1996 at the San Francisco International Echinoderm Conference Dr. Steve Stancyk and C. Muir at the University of South Carolina and Dr. Toshihiko Fujita of the National Science Museum in Tokyo presented some fascinating data showing the very abundant deep-sea brittle star Ophiura sarsicapturing and then swarming over and DEVOURING fish and shrimp as they got too close to the abundant carpets of brittle stars on the deep-sea bottom!!! Here was my blog post about back in 2008!

I remember seeing the presentation of this talk at San Francisco State University. The room was Standing Room ONLY! EVERYONE had to see the famous video of the brittle stars capturing swimming prey!!

BUT ! Dr. Stancyk has graciously NOW permitted his VIDEO of this event to be put up on Youtube making it AVAILABLE FOR THE FIRST TIME!!Basically... at about 4:48, a myctophid fish (and later a squid) gets too close to the "brittle star carpet", gets caught in a loop by the arm, gets DRAGGED down and then overcome by DOZENS of brittle stars!!!

Perhaps the most...striking part of this and the Okeanos Explorer video is how.. BRUTAL the brittle stars are when finally tearing apart their prey. Ophiura sarsi was literally rending those fish and squid apart!

About Me

I pursue starfish related adventure around the world with a critical eye and an appreciation for weirdness.
Support has been courtesy of the National Science Foundation but the views and opinions presented herein are mine and do not reflect the opinions of them or any affiliated institutions.
Need to hire an invertebrate zoologist/marine biologist? Please contact me!